Method of treating soles



May'll, 1937. F. N. LA CHAPELLE 2,079,712

METHOD OF TREATING SOLES Filed Sept. 19, 1934 A J2 v ff IMl'l'mn y@ 2 A :LMMQLQLM Patented May Il, 1g37 UNITED STATES PATENT OFFICE METHOD OF TREATING SOLES Application September 19, 1934, Serial No. 744,697

21 Claims.

This invention relates to a method of treating soles for shoes to adapt the soles to flex freely in accommodating and conforming to the natural movements of the bones and muscles of the feet in the act of Walking. The invention also relates to improvements in shoes and shoe soles as articles of manufacture.

Shoe soles have been prepared in various Ways prior to their incorporation in shoes for the purpose of increasing the exibility of the soles and machines have been provided for use in breaking in shoes by bending the shoes back and forth repeatedly in simulation of the bending occasioned by the movements of the foot in Walking. In the case of unattached soles it has been customary heretofore to treat the soles in such a manner that the soles are flexed or otherwise acted upon more or less uniformly throughout their entire area or throughout a relatively large portion of their entire area. Such treatment resuits in rendering the soles limp and inert in places where they will not be required to bend or flex when attached to a shoe and where a certain amount of stiffness is often desirable. Moreover, such treatment has proved to be quite ineffective to insure the desired amount of flexibility in the regions where the soles should be capable of flexing freely in the completed shoes. On the other hand, the so-called breaking-in machines which operate upon the finished shoes are frequently ineffective and invariably have a tendency to strain unduly the means employed for attaching the soles to the shoes whether the latter comprises stitching, metallic or other fastenings, or cement.

One object of the present invention is to provide an improved method of treating soles, and particularly leather soles, prior to their attachment to shoes which will render the soles capable of b-endingor flexing freely in the region of the break between the shank and forepart portions of the soles after the soles have been incorporated in the shoes.

With this object in view, the present invention provides an` improved method of treating unattached soles which comprises the step of stressing throughout the full width `of the sole the portion within which is located the area where the break between the shank and forepart will occur when the sole is nexed in the act of walking, While constraining the other portions of the sole against such treatment. In accordance with my invention the stressing of the sole substance in the portion referred to may be effected by a stretching operation or by a compressing operation and, as herein exemplified, the substance of y the sole is both stretched and compressed, in directions lengthwise of the sole, in the course of preparing it for incorporation in a shoe.

When the bottom of the shoe is bent more or less sharply from its normal substantially at condition, as when the shoe is flexed in the act of Walking, the shoe bottom is necessarily stretched at its outer side and compressed at its inner side. In shoes having inner and outer soles, the marginal portions of the latter, together with the overlasted margins of the upper, are secured together by means of stitching, ce-` ment or other fastenings, and when the shoes are flexed in walking the stitching or cement tends to prevent the inner and outer soles from moving or creeping longitudinally relatively to each other. Accordingly, as the soles bend, most of the resulting stretching is confined to the outsole while most of the resulting compression is conned to the insole. In order therefore to facilitate the flexing of the bottoms of such shoes the present invention contemplates treating outsoles and insoles differently to the extent of leaving the treated portions of outsoles in longitudinally compressed conditions so` that they will be capable of stretching freely as they will be required to do when they are bent out of their normal conditions by the flexing of the finished shoes, and leaving the treated portions of insoles in longitudinally stretched conditions so that they can be more freely and readily compressed as will be required when they are subsequently bent from their normal conditions in the act of Walking.

In practice, as herein illustrated, an unattached sole to be treated is firmly clamped at opposite sides of the region near the junction of the shank and forepart portions of the sole so that when the unclamped portion of the sole is treated the effect of the treatment will not extend to the clamped portions of the sole. The treatment of the sole may comprise a plurality of alternate stretching and compressing operations upon the portion which is to be operated upon until the desired degree of flexibility has been imparted thereto. In the case of leather soles it has been found to be advantageous to have the soles in a suitably tempered or moistened condition before subjecting them to stress and the treatment results in disrupting the fibrous structure of the leather as by breakin-g up or weakening the natural adhesive bond which unites the fibers or so displacing or otherwise modifying their normal disposition and arrangement as to produce a condition more favorable to the desired flexing of the sole in the shoe.

The invention also provides an improved article of manufacture consisting of an unattached insole of fibrous material, such as leather, having its substance stretched in directions edgewise, for example, lengthwise of the sole throughout the width and thickness of the sole in that portion only which is in the vicinity of the junction of its shank and forepart.

Theinvention will be explained with reference to the accompanying drawing, in which y Fig. 1 is a plan view of apparatus such as may advantageously be employed in the treating of an outsole;

Fig. 2 is a longitudinal sectional view of the apparatus shown in Fig. 1, illustrating the method of clamping the forepart and the heel and shank portions of the sole;

Figs 3 and 4 are sectional views similar to Fig. 2 but illustrating further steps in the practice of my method; and

Figs. 5 and 6 are sectional views illustrating the use of the apparatus in an alternative method of treating outsoles-in accordance with my invention.

' In practicing my improved method in its application to the treatment of leather soles, it is desirable that the soles should be in a suitably tempered condition before being operated upon in order that they may respond readily to the treatment without risk of injury to the fibers of the leather. The tempering of the soles for this purpose should involve initial wetting or moistening operations and subsequent draining and mulling operations, and the same may be accomplished in any well-known manner. Care should be taken, however, to insure against the presence of excessive moisture in the soles while they are being subjected to the stretching and compressing operations.

Referring now to the drawing, my improved method is therein exemplified as being carried out with the .iid of apparatus comprising a sole supporting table ill, a forepart clamp I2 and a heel part clamp Ill for cooperating with the table in clamping the forepart and the heel and shank portions respectively of a sole, a plunger I E which has a rounded work-engaging surface I8 and which is operable between the clamps I2 and I4 and in line with an opening 2i) in the table I9 for stretching the sole in the region near the junction of its shank and forepart, and two plungers 22 and 24 having flat work-engaging surfaces 2G for cooperating one with the other in compressing the sole in the region just referred to, the plunger 22 being operable through the opening 2l.) in the table I0 while the plunger 24 is adapted to be substituted for the plunger I6 and to be operated in the same manner as the latter between the clamps I2 and It. As shown, the clamps I2 and I4 are carried at the lower ends of vertical rods 28 while the plungers I6, 22, and 24 are carried by vertical rods 3B, the rods 28 and 3B being movable axially by any suitable means (not shown) whereby the clamps and the plungers may be moved to and from operating positions. The plungers I6 and 24 are adapted to be removably tted upon their respective rods so that they may be used interchangeably as required. The several plungers are formed each with lateral flanges 32 adapted to cooperate with adjacent portions of the clamps I2 and I4 to determine the operative positions of the plungers. The plungers are shaped and arranged as clearly indicated in Fig. 1 so as to extend entirely across a sole or sole blank, such as the block outsole A (Fig. l), each plunger having its opposite sides disposed substantially parallel to a line such as that indicated at B in Fig. l and which may be referred to as the break line of the sole, i. e., the line where the junction or break will occur between the shank and forepart portions of the sole when a shce in which the sole is incorporated is flexed in the act of walking. As shown in Fig. 5, the table B is provided with a pair of sole positioning plates 34, the plates being arranged to engage the opposite ends of a sole or a sole blank for a purpose to be hereinafter explained and the screws 36 extending through horizontally elongated slots 38 in the plates 3d so that the plates may be adjusted to adapt them for use in connection with soles of different lengths.

in practicing my improved method in its application particularly to the treatment of leather outsoles with the aid of the above-described apparatus, an outsole, for example the block outsole A, in a suitably tempered condition, is placed upon the table IG, as shown by dotted lines in Fig. l, in such a position that the break line B of the sole will be substantially parallel to the opposite sides of the plunger I6. Assuming that the sole to be operated upon is a sole for a right shoe, it will be apparent that the same apparatus may be employed in connection with a sole for a left shoe by the simple expedient of turning the sole over so that its outline will correspond to that of the outline of a sole for a right shoe. The clamps I2 and I4 are next operated to clamp the forepart and the heel and shank portions of the sole firmly against the table Ill, leaving exposed for treatment only a relatively narrow portion A (Fig. 2) extending across the sole near the junction of its shank and forepart. The lower plunger 22 being in the retracted inoperative position shown in Figs. 2 and 3, the upper plunger I6 is forced downwardly into the position shown in Fig. 3 which is determined by engagement of its flanges 3:2 with the clamps I2 and I4.

This movement of the plunger I6, while the sole is held rmly clamped against the table at opposite sides of the plunger, results in stretching longitudinally of the sole that portion of the sole which lies between the clamps. Preferably the plunger I6 is so designed and operated that the portion of the sole operated upon is stretched as much as practicable within the limits of elastic recovery of the leather. In this manner the brous structure of the leather is disrupted and the bers are displaced or stretched in directions toward the ends of the sole, thereby making the treated portion of the sole more limp and flexible than the rest of the sole. The portion of the sole which has thus been stretched is not, however, capable of being readily stretched still further as it must necessarily be stretched if, after being incorporated in a shoe, it is to bend as required in conforming to the movements of the bones and muscles of a foot in the act of walking. Accordingly, in order that the sole shall be rendered capable of thus bending freely after it has been attached to the shoe, the portion of the sole which has already been initially stretched as described is now subjected to a nal compressing operation. As herein illustrated, this iinal compressing operation is effected by the cooperative action of two flat-faced plungers 22 and 24, the plunger 24 having been substituted for the round-faced plunger I6 which was employed to stretch the sole and the two plungers It may be found in practice that 22 and 24 coacting, as illustrated in Fig. 4, to flatten out the bulge produced by the earlier stretching operation. Inasmuch as the portions of the sole at opposite sides of the bulge are still held against longitudinal movement by the action of the clamps H4, the flattening out of the bulge in the sole results in compressing the material constituting the bulge, thereby further disrupting the fibrous structure of the leather and, it is believed, either displacing the fibers in the portion being operated upon in directions lengthwise and away-from the ends of the sole, or crowding them together so as to accumulate longitudinal fullness in that portion of the sole which is ultimately to be flexed when the sole is bent in walking. The treated portion of the outsole is now in such a condition that it is Vcapable of stretching freely in exactly the manner in which it will be required to stretch when, after having been incorporated in the shoe, it is bent quite sharply out of its normal substantially flat condition as the shoe is flexed in walking. either the stretching operation or the compressing operation alone may be suicient to produce the desired flexibility in the sole. On the other hand, it may be found desirable alternately to stretch and compress the leather a number of times, in order more effectively to disrupt the brous structure of the leather. However, for the reasons above pointed out, it is preferred that the final preparatory operation performed upon an unattached outsole shall be a compressing action as distinguished from a stretching action so that the fibrous structure' shall be left in a contracted condition and therefore capable of stretching or elongating freely lengthwise of the sole to facilitate such bending of the sole as is to take place in the finished shoe.

It is to be noted that the above-described treatment of an outsole is such that neither the stretching operation nor the compressing operation results in any alteration of the length of the sole, this being a feature of substantial importance inasmuch as it obviates thenecessity of making allowance for any shortening or lengthening of the soles, as well as avoids such waste of material as might result from any shortening of the sole.

As an alternative method of treating an outsole to facilitate the flexing of the Sole in a shoe, I may secure the desired displacing of theV fibers or disrupting of the fibrous structure of the sole by compressing the sole in the vicinity of its break line without anypreliminary stretching of the same, therebyinsuring that the treated portion will be left with its bers abnormally compressed or crowded together lengthwise., of the sole. I may advantageously carry out this alternative method of procedure with the aid of the above-described apparatus fitted, as shown in Fig. 5, with the plates 34 in position toengage the opposite ends of the sole, the Yplates having been first adjusted so that the distance between them is somewhat less than the length of the sole to be operated upon. With the plates 34 rigidly clamped in such adjusted positions an outsole is placed upon the table lll `|between the plates, the outsole thereby being caused to assume the upwardly buckled condition shown. The clamps l2 and I4 are then lowered to flatten out and clamp the forepartand heel and shank portions, respectively, of the sole, in the same manner as shown in Fig. 6, this operation causing the buckling of the sole to be concentrated in the space between the clamps I2 and I4. Thereafter the upper plunger 24 is lowered to cooperate with the raised lower plunger 22fin compressing and flattening out the buckled portion of the sole so that the sole will then appear substantially as indicated in Fig. 4. This operation results in abnormally compressing or contracting the material in the portion of the sole which is to be flexed in the finished shoe and may be found sufficient to facilitate such flexing without any preliminary stretching of the sole.

With respect to the treatment of insoles it should be pointed out that many insoles are made of leather of such inferior or spongy character that little if any treatment of the insole is necessary in order to render them capable of flexing freely in the finished shoe. However, in cases where the insoles areto be made of substantial thickness and of a good quality of grain leather, it may be desirable to subject them to special treatment in order to facilitate the ilexing of shoes in which they are incorporated. In treating such an insole I may merely stretch the portion iinished shoe, for example, by proceeding as illustrated in Figs. 2 and 3, and as already described with reference to those figures in connection with the preliminary stretching of the corresponding portion of an outsole, thus leaving the insole L capable of being compressed freely in the portion referred toas the shoe is bent in walking. A1- ternatively, I may subject the insole to both stretching and compressing operations, preferably, however, iirst compressing and later stretching the insole so that it will be left in a finally stretched condition and thus be more readily compressible as the bottom of the shoe is bent in the act of walking. In carrying out this alternative method I may proceed as already described in connection with the treatment of an outsole and with reference to the apparatus shown in Figs. 5 and 6, first clamping an insole positioned between the end plates 34, thereby producing an upward bulge in the vicinity of the break line of the insole similar to the bulge indicated in Fig. 6. Subsequently this upward bulge in the insole is flattened out by the cooperation of the two fiatfaced plungers 22 and 2'4 in a manner such as that already described in connection with the i treatment of the outsole, and indicated in Fig. 4. Thereafter the round-faced plunger IB will be substituted for the flat-faced upper plunger 24 and operated as indicated in Fig. 3 to stretch the previously compressed or contracted portion of the insole. It will be seen that the insole is thus subjected to both stretching and compressing operations as in the case of the outsole but with the exception that the insole is left in a finally stretched condition instead of in a iinally compressed condition. An insole thus treated will be readily compressible as required to adapt it to be bent out of a normal substantially flat condition as required in order that it shall conform to the flexure of a foot in the act of walking.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent of the United States is:

1. That step is preparing an unattached sole for incorporation in a shoe which consists in stressing the substance of the sole throughout the full width of the sole in a direction edgewise of the sole and in that portion which is in the immediate vicinity of the junction of the shank and forepart of the sole, while constraining the which is to be rendered flexible in the other portions of the sole ment.

2. That step in preparing unattached soles to facilitate flexing of the soles in shoes which consists in stressing the substance of the sole throughout the full width of the sole in directions lengthwise of the sole and in a relatively narrow portion extending across the sole within which is located the area where the break between the shank and forepart of the sole will occur when the sole is incorporated in a shoe, while constraining the other portions of the sole against said treatment.

3. That step in preparing an unattached sole for incorporation in a shoe which consists in stressing throughout the full width of the sole the portion within which is located the area where the break between the shank and forepart will occur when the sole is flexed in the act of walking while constraining the other portions of the sole against such treatment.

4. That step in preparing a sole for incorporation in a shoe which consists in streaching the substance of the sole throughout the full width of the sole in that portion of the sole which is in the immediate vicinity of the junction of the shank and forepart of the sole, while constraining the other portions of the sole against stretching.

5. That step in preparing a sole for incorporation in a shoe which consists in stretching the substance of the sole lengthwise of the sole and throughout the full width of the sole in that portion which is in the immediate vicinity of the junction of the shank and forepart of the sole, while constraining the other portions of the sole against stretching.

6. That step in preparing an unattached sole for incorporation in a shoe which consists in compressing the substance of the sole in directions edgewise of the sole and throughout the full width of the sole and rin that portion only which is in the immediate vicinity of the junction of the shank and forepart of the sole.

7. That step in preparing an unattached sole for incorporation in a shoe which consists in compressing the substance of the sole in directions lengthwise of the sole and in that portion only which is in the immediate vicinity of the junction of the shank and forepart of the sole.

8. That step in treating unattached outsoles to prepare them. for incorporation in shoes Which consists in initially stretching and finally compressing longitudinally of an outsole the material in that portion only of the outsole which is to be flexed in the act of walking.

9. That step in treating unattached insoles to prepare them for incorporation in shoes which consists in initially compressing and finally stretching longitudinally of an insole the material throughout the width of the sole and in that portion only of the insole which is to be iieXed in the act of Walking.

10. That step in preparing an unattached leather sole for incorporation in a shoe which consists in effecting relative displacement of the fibers of the leather in directions lengthwise of the sole throughout the width of the sole and in that portion of the sole which is in the vicinity of the junction of the shank and forepart of the sole, while clamping the rest of the sole to constrain it against such action from taking place therein.

11. That improvement in methods of preparing unattached leather soles for incorporation in against such treatshoes which consists in tempering a sole and, while the sole is still in a tempered condition, relatively displacing the fibers of the leather in directions lengthwise of the sole throughout the width of the sole and in that portion of the sole which is to be flexed in the act of walking, while constraining the rest of the sole against such treatment.

12. That step in preparing an unattached leather sole for incorporation in a shoe which consists in relatively displacing the bers of the leather in the vicinity of the ball portion of the sole in directions lengthwise of the sole throughout thewidth of the sole while constraining the other portions of the sole against such treatment.

13. That step in preparing an unattached leather sole for incorporation in a shoe which consists in weakening the bond between the fibers of the leather throughout the full width of the sole and in that portion of the sole which is in the immediate vicinity of the junction of the shank and forepart of the sole, while clamping the other portions of the sole to prevent such action from taking place therein.

14. That improvement in methods of preparing unattached leather soles for incorporation in shoes which consists in moistening a sole and, while the sole remains in a moistened condition, weakening the bond between the fibers of the leather throughout the full width of the sole and in that portion of the sole which is in the immediate vicinity of the junction of the shank and forepart of the sole, while clamping the rest of the sole to prevent such weakening action from taking place therein.

15. That improvement in methods of preparing unattached soles for incorporation in shoes shank and forepart of the sole against longitutinal movement, flattening out said buckled portion.

16. That improvement in methods of treating leather outsoles which consists in buckling an outsole transversely, constraining the buckled outsole endwise to prevent it from returning to its normal unbuckled condition, clamping the forepart and shank portions of the buckled outsole in a common plane to remove the buckled formation from them and concentrate it in a relatively narrow intermediate portion located between said clamped portions, and subsequently flattening said intermediate portion thereby modifying the disposition of the bers therein in a manner enabling said portion to flex readily in a shoe.

17. 'I'hat improvement in methods of treating fibrous sheet material such as leather which consists in forming a bulge in a selected portion of a piece of such material, and subsequently depressing the bulge while constraining against displacement the material at opposite sides of and immediately adjacent to the bulge, thereby compressing the material constituting the bulge in directions edgewise of said piece.

18. That improvement in methods of treating leather soles which consists in buckling a sole to reduce one of its major dimensions, clamping two separated portions thereof in a common plane to remove the buckled formation from them and concentrate it in the intermediate portion, and flattening said intermediate portion without reducing its thickness, thereby modifying the arrangement of the bers therein in a manner adapting it to ex more easily in said intermediate portion.

19. That improvement in methods of treating soles made of iibrous material such as leather which consists in reducing the length of a sole by longitudinal compression` of the` sole in a degree suiiicient to modify the: interlaced arrangement of the loers and at the same time constraining the major surfaces ofl the sole so that at least one of them will be substantially flat when the maximum degree of such longitudinal compression is attained.

20. As an article of manufacture; an insole of fibrous material having its substance stretchedv in directions edgewise of the sole throughout the? width and thickness of the sole in that portion only of the sole which is in the vicinity of the junction of the shank and forepart of the sole.

21. As an article of manufacture, an insole of fibrous material having its substance stretched in directions lengthwise of the sole throughout the Width and' thickness` of the sole in that portion only of the sole which is in the vicinity' ofthe junction of the shank and forepart of the sole.

FRED LA CHAPEIIILIEv 

